1. Field of the Invention
The present invention relates to a liquid conveying catheter and in particular, to a liquid conveying catheter for introducing a predetermined liquid into a living body and collecting a liquid from the living body.
2. Description of the Related Art
Conventionally, in the medical field, catheters have been used for inspection and curing. Currently, the catheters are used for the respiration organ, digestion organ, circulatory organ, and other organs.
FIG. 8 shows a conventional liquid conveying catheter 100 comprising a liquid supply tube 101 for introducing a predetermined liquid into a living body and a liquid collecting tube 102 for collecting a surplus portion of the liquid. An insert end of the liquid supply tube 101 and an insert end of the liquid collecting tube 102 are combined together for insertion. The other end of the liquid supply tube 101 is connected to a liquid reservoir (not depicted) and a positive pressure pump 103 for feeding the liquid to the insert end. The other end of the liquid collecting tube 102 is connected to a negative pressure pump 104.
The insert end of the liquid supply tube 101 and the insert end of the liquid collecting tube 102 are inserted into a living body. A liquid is supplied via the liquid supply tube 101 by the positive pressure pump 103, and a surplus liquid is collected via the liquid collecting tube 102 by the negative pressure pump 104.
Here, the liquid collecting tube 102 is often collapsed by a negative pressure, depending on the material constituting the liquid collecting tube 102, disabling liquid flow in the liquid collecting tube 102.